Percentage of Birth order 3 and above (X₂): Higher order births are risk for mother and child. If the higher order births are more it’s an indication of high fertility. RCH survey shows that 43.9 percent of the total births in India were of order three and above. The proportion was highest in Uttar Pradesh (60 per cent) and lowest in Kerala (18 per cent). In the states like Arunachal Pradesh, Bihar, Meghalaya, Mizoram, Rajasthan and Uttar Pradesh the percentage of 3 and higher order births ranged between 50 – 60 percent. In Orissa and Madhya Pradesh the same was recorded at 46 percent and 45 percent respectively. The North Cachor Hills district in Assam recorded the highest percentage of births (73.7 per cent) of order 3 and above followed by Tuensang district in Nagaland (73.2 per cent), South Garo Hills district in Meghalaya (68.2 per cent), East Kameng district in Arunachal Pradesh (67.9 per cent), Bareilly in Uttar Pradesh (67.40 per cent). Pathanamthitta district in Kerala recorded the lowest percentage (1.9 percent) of birth of order 3 and above.

 Accordingly the index of birth order 3 and above is computed by fixing the upper limit of 73.7 and lower limit of 1.9. 

 Index₂ = 100*(73.7- X₂) / (73.7-1.9) 

           = 100*(73.7 - X₂) / 71.8 

Where X₂ is the proportion of births of order 3 and above in a particular district. Lower the percentage of birth order 3 and above, higher the index value.